MT-MR PLATINUM. POINT TO POINT AURAL RADIO RELAY SYSTEM
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Materials:
Inner Conductor ..................................................................................................................................... Copper.
Outer Conductor .................................................................................................................................... Copper.
Diameter (incl. PVC sheat) ............................................................................................................................... 28 mm.
Diameter (Outer cond.) .................................................................................................................................. 24.9 mm.
Minimum Bending Radius ............................................................................................................................... 250 mm.
Minimum Number of Bendings ................................................................................................................................. 15
Bending Momentum ...................................................................................................................................... 16.3 N/m.
Weight ......................................................................................................................................................... 0.49 Kg/m.
Resistance to Stress ........................................................................................................................................ 147 Kg.
Resistance to Crush .................................................................................................................................. 1.4 Kg/mm.
Any authorized Antennas Catalog contains these and other Technical Specifications in event of using other type of
transmission line. This is only an example of a possible use of a certain type of transmission line.
In our illustrative example, if we use two turrets having 20 m. height each, we have 20 meters of transmission line
length, plus additional 10 meters calculated to acceed the Station site and internal runways within Station building.
Total = 30 meters representing a loss of :
30 x 6.46
AL = = 1.94 dB [per Station]
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By the other hand, it's allowable to assume 1 dB per station for connectors & coupling losses, so we have 2.94 dB
of total line & connector losses per station.
1.6.- Calculation of Antennas.
Final system calculation is the required Antenna gain at each Station in order to keep the link's reliability and
received signal level.
Assuming that we have a Transmitter Power output of 4 watts, that is +36 dBm, and following signal path from
Transmitter output to Receiver input, we can build the following expression:
(3) P
t
- A
lt+con.
+ G
at
- ß + G
ar
- A
lr+con
. = S
rec
.
Where:
P
t
= Transmitter Power Output in dBm (or dBw)
A
lt+con.
= Transmission line & connectors losses at Transmitter end.
(in dB).
G
at
= Transmitter antenna gain (in dBi)
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ß
= Free Space Attenuation (in dB)
